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A reference to the populated Hashtable object referred to by piano is returned when the for loop terminates at the bottom of Listing 18 .

Listing 18 also signals the end of the getPiano method and the end of the class named PlayerPiano01 . However, we aren't finished yet. We need to go back and examine the code in the method named makeMusic that we put on the back burner a little earlier.

Beginning of the method named makeMusic

The method named makeMusic begins in Listing 19 . This method transforms the notes for a clef into an array of amplitude values. This method doesn't know the difference between a treble clef and a bass clef.It is called once to transform the treble clef at the bottom of Listing 12 . It is called again to transform the bass clef in Listing 13 if the user provides a text file containing bass clef data.

Listing 19 . Beginning of the method named makeMusic.
void makeMusic(ArrayList clef,int beatsPerSec){ double gain = 4000.0;//Set the output volume to a reasonable level.//Get a hashtable that maps note names into note frequencies from A2 // through A7. Note that the name "X" is used to indicate a period of// silence or a rest, so it is appended onto the end of the hashtable with // a frequency of 0.0.//Frequency values can be checked against // http://www.phy.mtu.edu/~suits/notefreqs.html.Hashtable piano = getPiano(); piano.put("X",0.0);//Miscellaneous variables double freq = 0;int beats = 0; double scaleFactor = 0;

Nothing in Listing 19 should require an explanation beyond the embedded comments.

Process each array containing duration and note names in the ArrayList object

Listing 20 shows the beginning of a while loop that uses an iterator to process each array containing duration and note names in the ArrayList object

Listing 20 . Process each array containing duration and note names in the ArrayList object.
Iterator iter = clef.iterator(); while(iter.hasNext()){//Get the next array containing duration and note names String[]array = (String[])iter.next();//Get the duration of the note in beats beats = Integer.parseInt(array[0]);

The code in Listing 20 accesses the next array and then extracts the duration (in beats) from the array and stores it in the variable named beats .

Process each sample

Listing 21 shows the beginning of a for loop that is used to process each sample that makes up this note. The output sampling rate is constant. Therefore,notes with a short duration comprise fewer samples than notes with a long duration.

Listing 21 . Process each sample.
for(int cnt = 0; cnt<beats*audioParams.sampleRate/beatsPerSec; cnt++){ //Compute the time for this iteration to use when evaluating the// cosine function. double time = cnt/audioParams.sampleRate;double sum = 0;//sum of values for this iteration

Process each piano key that is pressed

Recall that a human piano player can press several keys simultaneous, as in (9,A3,C4,E4) at the end of Listing 30 . In this case, the piano player would press threekeys simultaneously on the piano keyboard and hold them down for nine beats.

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
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RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
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industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
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LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
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LITNING
scanning tunneling microscope
Sahil
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Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
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what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
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Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
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Adin
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biomolecules are e building blocks of every organics and inorganic materials.
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research.net
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Introduction about quantum dots in nanotechnology
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nano basically means 10^(-9). nanometer is a unit to measure length.
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Damian Reply
absolutely yes
Daniel
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Source:  OpenStax, Accessible objected-oriented programming concepts for blind students using java. OpenStax CNX. Sep 01, 2014 Download for free at https://legacy.cnx.org/content/col11349/1.17
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